1. Technical Field.
The present invention applies to a device that can attach to and release an object such as a ring in general, and to devices that can attach to and release such objects as they may be found in a marine application in particular.
2. Background Information.
The problem of hooking onto an attachment point from a distance is encountered in mountain-climbing, speleologie and above all in the mooring of boats (this list is in no way exhaustive). The idea of automatically hooking onto a ring or buoy by means of a snap-hook, where the latch of the snap-hook is held in the closed position by a spring, has existed for a long time. However, the problem of re-opening the snap-hook and releasing it from the ring has only been partially resolved.
The U.S. Pat. No. 653,021 describes a snap-hook where the opening of a latch can be operated from a distance. However, with this device the force exerted by the boat on the mooring ring is transmitted via the mechanism of the latch. Thus, all parts of the device, including the closing mechanism of the latch, must be built to resist this force which may amount to several hundred Newtons. Consequently, the device is massive, heavy and expensive to manufacture. In addition, depending on the sea-state, the jerking and tugging caused by waves and wind will constantly activate the opening mechanism, causing it to wear out prematurely.
U.S. Pat. No. 4,595,223 proposes a snap-hook where the opening of the latch can be effected from a distance by means of a long tool specifically intended for this use. However, it should be borne in mind that when releasing the mooring, depending on the sea-state and the wind strength, a force of several hundred Newtons may be exerted on the hook, so that even if the latch is opened from a distance, the hook still has to be detached from the mooring ring. In effect, due to the traction exerted by the boat on the hook, the boat will still be attached to the mooring ring even if the latch is open.
More recently other devices have been proposed where the hook consists of two main parts, one of which (typically the part which holds onto the mooring buoy) pivots around an axis. A mobile element locks the two parts of the hook together. To release the mooring, the mobile element is activated by pulling on the control mechanism by means of a rope or a boat-hook, so as to allow the part of the hook attached to the buoy to pivot freely around its axis. European patent application EP 0644340A3 discloses an example of this type of device. The main inconvenience with such a device is its lack of security: there is always the possibility of involuntary release of the mooring due to an accidental pivoting of the part of the hook attaching the boat to the buoy. This could result from a faulty maneuver, or from breakage or dysfunction of one components of the hook""s mechanism, which could have serious consequences. In addition, these relatively complex mechanisms are expensive to manufacture. It should also be taken into account that, because of the lack of security, these devices are only intended for a temporary, attentively surveyed mooring at the moment of arrival or departure.
It is evident that the ideal device for attaching and releasing a boat has not yet been invented. Ideally, such a device would be simple, robust and reliable, and would also be suitable for semi-permanent, non-surveyed mooring of the vessel.
The aim of the present invention is to provide a means for overcoming the above-mentioned shortcomings. To this end, the present invention proposes a snap-hook device having a closed clasp that includes a hook to which a latch is hinged about an axis perpendicular to the plane of the clasp, a stop to limit the pivoting movement of the latch in the closed position of the clasp, and an elastic means of exerting a torque between the latch and the hook in order to hold the latch against the stop. The latch includes two parts both hinged around an axis perpendicular to the plane of the clasp, at least one stop to limit the rotational movement of the parts in relation to one another, and a second elastic means to maintain a torque between the two parts of the latch in a direction opposite to that of the torque exerted between the latch and the hook and tending to continuously hold the parts against the stop.
These and other objects, features, and advantages of the present invention will become apparent in light of the detailed description of the present invention.